Missed Blocks

Overview

The process is as follows:

  1. Identify the slot.
  2. Investigate the Vouch logs.
  3. Verify if MEV and follow up with relay.

Identify the slot

This is done by logging on to the client box and running the missed blocks command:

  1. su ops
  2. acli attestant missedblocks --start-range=2026-06-09T05:00:00 --end-range=2026-06-09T12:47:00

You need to set a suitable time range for the missed block. Check the KPI dashboard for the time of the missed block and set a time range about an hour each side. This is because it takes time to finalise so the time the KPI dashboard detects the missed block is a bit behind the actual time.

This should give an output similar to the following:

From: slot 14513000 (2026-06-09T00:00:00 UTC)
To:   slot 14514000 (2026-06-09T09:00:00 UTC)
1 missed block(s):
Timestamp            Slot      Pod    Customer             Validator  Fee recipient
2026-06-09T00:40:00  14513000  pod-2  1234567891234578912  1778151    0x2323232323232323232323232323232323232

Investigate the Vouch logs

Find the active host for the pod identified in step 1 and grep the logs for the slot identified in step 1. This will likely show a proposal log like so:

{
  "level": "info",
  "service": "blockrelay",
  "impl": "standard",
  "slot": 14513000,
  "provider": "https://bloxroute.max-profit.blxrbdn.com",
  "value": "3580000000000000",
  "value_delta": "0",
  "score": "3580000000000000",
  "score_delta": "0",
  "selected": true,
  "time": "2026-06-09T07:00:00.000Z",
  "message": "Auction participant"
}

NB: There may multiple Auction participant logs for the same slot - be careful to pick the one with selected: true

If the above is found then this was a relay slot - proceed to step 3.

If not a relay slot then there must have been an issue with local block production. For local block production we need to check for network issues, errors in the vouch logs and errors in the beacon nodes.

Verify if MEV and follow up with relay

If the above was a relay slot then we need to ensure we signed the block in time. To do this open jaeger, Set the Service to Vouch, set the Operation to Proposal and set the Tags to slot=14513000 (use the actual slot number found in step 1). This should give you the trace for the proposal.

Once you have this you can check how far into the slot we signed. We should sign within 2 seconds. You can see from this image that we signed around 1.75 seconds into the slot:

Missed Block Trace

If we signed within 2 seconds we should follow up with the relay and ask for a refund.